I stay at the Flamenco whenever I visit now days - we went to the Allegro once just to see and had to PAY for the drinks. Its the same chain yes - but you dont really get any special treatment!
Go to the front desk at the Flamenco and ask for Erik. He is the Room manager from Jack Tar on loan to the Flamenco while they are remodeling. Tell him what you want to do and he will arrange it. I do this all the time at Occidental resorts.
I´d say it is not for sure. And for sure not a treatment for anyone.
The same chain yes, but different economy, finance etc, they are separated in that matter.
For "just anyone" or if this will become a frequent request, you would need to pay.
I worked in a chain hotel that has 5 hotels but the guess of one of them could eat and drink the other 4, but the guess of the other 4 only could use the facilities of the one of them, no drink, no eat. Maybe is the case will depend wich one you are staying.
